Fix DelayDiffEq version to 5.70.0

The version was incorrectly bumped to 5.71.0, skipping 5.70.0.
The registry requires sequential version numbers.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: ChrisRackauckas

lib/DelayDiffEq/Project.toml

@@ -1,7 +1,7 @@
 name = "DelayDiffEq"
 uuid = "bcd4f6db-9728-5f36-b5f7-82caef46ccdb"
 authors = ["Chris Rackauckas <accounts@chrisrackauckas.com>"]
-version = "5.71.0"
+version = "5.70.0"
 
 [deps]
 ArrayInterface = "4fba245c-0d91-5ea0-9b3e-6abc04ee57a9"